Finger-exercising device



March 31, 1931. L. ROTH 1,798,386

\ FINGER EXERCISING' DEVICE Filed. Dec. 22, 1928 o v a 5 a 1g i v I ip} I? f5 Y r 3 I" x Patented Mar. 31, 1931 UNITED STATES EUGENE LOUIS ROTH, F ANTWERI, BELGIUM FINGER-EXERCISING DEVICE Application filed December 22, 1928. Serial No. 328,028.

The present invention has relation to an improved device of the kind described in the U. S. patent application Serial No. 240,860 and designed to develop, improve or correct the relation between the individual strength of the various fingers of the left and right hands, this device becoming useful every time it is desired to obtain a particularly well developed strength, suppleness and independence of the fingers.

All those who, on account of their regular occupation, have to thoroughly exercise the fingers, know by experience that the greatest difiicult'ies to overcome are:

(1) The difference between the natural strength of the various fingers;

(2) The lack of independence of the individual fingers;

(3) The stiffness of the fingers and of the wrist.

The first of these difiiculties brings about the greatest drawbacks and its removal will also solve the problems set up by the second and third difiiculties. It is indeed the difference between the strength of the various fingers that has guided'the searches and the experiments carried out by the greatest pedagogues, medical doctors and virtuosos. The dumb exercises for stringed instruments have been up to the present time the most interesting methods forming the basis of the means employed to remove said first difiiculty. The whole matter is based on an unchanging principle: every normal hand will show forth, on account of its anatomical constitution, this peculiarity of unequal strength of the various fingers. This peculiarity has a result to call forth inopportune surplus strength or to take away strength from the stronger fingers, when the strength of certain weaker fingers has to be particularly emphasized.

Suppose that, for instance, the five fingers of one hand (let us give them the numerals 1 to 5 starting from the thumb) exert a certain definite pressure, and let us find out how the various fingers will behave when an increased pressure is exacted from certain weaker fingers, for instance finger 4 or 5.

It will be seen then, (at least if the hand has not been perfectly trained) that the strength brought over to the fingers 4 and 5 has altered the pressure exerted by the other fingers:

(l) A non-desired movement of the wrist,

which comes to the help of the weaker finger, will take away from the other fingers their individual working liberty;

. (2) The surplus strength, instead of working exclusively upon the fingers for which it is intended, will influence all the other fingers, above all the strongest fingers, which react much more easily than the weakerfingers.

When exercising the fingers, it will thus be noticed that the difference between the natural strength of the various fingers has as logical result to hinder the independence of the fingers and to bring forth a stiffness of the hand and of the wrist; the stronger fingers hold the weaker fingers in check.

These disadvantages are removed by the device according to the U. S. patent application Serial No. 240,860, by reducing the difference between the strength of the various fingers and by developing simultaneously the strength, suppleness and independence of the fingers.

For this purpose, said device is provided with resistances opposed to actions exerted by the fingers, different resistances being provided for the various fingers, the arrangement being such that the resistance opposed to the action of the weaker fingers is greater than that opposed to the stronger fingers.

According to the invention, these resistances consist of counterweights, which can be adjusted in accordance with the natural in dividual strength of each finger. When the difference between the strength of the various fingers decreases, the counterweights are altered in such a manner that the resistances opposed to the actions of the various fingers tend to become the same for all fingers, so as to become finally exactly the same as soon as the fingers have been perfectly developed. This adjusting of the resistances which have to be overcome by the fingers is combined,

with controlling means, whereby the slight- 1 est movements of any one of the fingers can be observed.

For this purpose, indicators, actuated by the members which are actuated upon by the fingers are provided.

The exercises provide determined pressures for the various fingers, while the control means allow it to be ascertained at the same time Whether said pressures have been correctly executed, so as to find out if the wrist or the other fingers have or have not participated in the exerted pressure.

In an embodiment of the invention, the device comprises a key-board, having a plurality of keys, upon each of which weights are arranged toact in: opposition to the ace tion of the various fingers upon the keys. Control. devices, which are actuated by the keys, consist of indicators capable of shifting behind openings provided in the front wall of the casing of the apparatus.

The invention: will be described in detail hereafter, with reference to the accompanying drawing, which gives, merely by way of example, an embodiment of the invention.

The figure of the drawing is a side view of the device, the casing being given in sec tion. I

With reference to this figure, the key 1 is arranged in a casing 2, part of the key extending inside the casing, part of it outside. The part of the key 1 extendingoutside the casing 2 isprovided with acelluloid or other white or differently coloured lining 3', upon which the finger exerts its pressure. about the pin a. On the inner end of the key 1 is provided a groove 5 of decreasing depth starting from the end of the key. In this groove 5 is inserted the lower end of a supporting element 6, which is pivotally mounted in the key 1. This support carries two rods 7 and 8. The upper end of the rod 7 passes through an opening provided in a longitudinal bar 9 extending at right angles to the direction of the key. Said bar 9 is loosely inserted on the various rods 7 of the keys and it is maintained in its position in the casing by means of two stops 10 provided on both lateral walls of the casing. The rod 8, which is of shorter length than the rod 7, is to receive the weights 11, providedwith axial holes for their insertion on the rod 8. These weights 11 are arranged on all the keys, different weigths being provided for different fingers and the arrangement being such that the heavier weights correspond to the weaker fingers. Besides, these weights can easily be removed and replaced by other weights. These weights will preferably bear a number indicating the strength to be ex erted on the other end of the key 1 tolift said weights when they are placed on the inner end of the key. The upward and down ward movement of the weights 11 and sup- -clifi'erent markings or colours.

The key 1 is capable of oscillating port 6 is guided by the rod 7 sliding in the hole of the bar 9. On the other hand, the front end of the key 1 is guided by means of a pin 12 secured to the key-bed or stop 13 and capable of entering a slot 14 provided in the key 1.

In the front wall of easing 2 are arranged a number of openings 15, each opening corresponding to a key 1. Behind these openings 15 are disposed indicators 16, hearing These indicators are capable of shifting behind the openings 15 and they are actuated from the keys 1. For this purpose, a support 17 is inserted in the groove 5 and pivotally mounted in the" inner end of the key 1. Said support 17 carries a rod 18, turned at its free end to form a hook engaging a hole 19, provided in one end of a lever 20, the other end of said lever carrying the indicator 16, which is preferably of cylindrical shape, the axis of the cylinder coinciding with'the rotation axis 21 of the lever 20. The rotation pin- 21 is pivotally mounted in bearings forming part of supports 22 secured to a longitudinal bar 23 extending at right angles to the direction of the keys. "This bar 23 is attached at both ends to uprights 2 forming part or secured to the walls of the casing 2.

lit is obvious that the movement of the indicators 16 may be different of that shown in the drawing, for instance, instead of being directed downwards, it may bexdirected upwards. it may also be horiZonta-linstead of vertical.

The backwall 25 of the 'casing'can be opened, so as to give access to the weights, which can be easily removed and replaced, without having to take out any part of the apparatus. A cover 26, hinged at 27 to the casing 2 is provided to shelter the keys when the apparatus is not in use.

The various grooves or slots 14, 5, etc., as well as the stops 13 for the front part of the key and 28 for the rear part of samecan be lined with felt or any other appropriate ma terial.

I claim: I

1. A. finger-exercising device to obtain and to preserve the normal relation between the ind vidual natural strength of .difierent fingers, comprising in combination: a casing, a keyboard with the keys to be depressed extended backwardly into the casing, movable indicators sliding inside the casing behind the front wall of same, a series of markings similarly disposed on each indicator, a longitudinal opening extending over the whole length of said front wall, a series of transmitting levers consisting of one for each key connecting said indicators with the keys and causing an indicator-to move downwardly in front of said opening when the corresponding key is depressed, adjustable weights renioyably arranged upon each key so as to act in opposition to the pressure of the finger on the key, and means for adjusting said weights by increasing or decreasing said weights, substantially as described.

2. A finger-exercising device to obtain and to preserve the normal relation between the individual natural strength of different fingers, comprising in combination: a casing, a keyboard with the keys to be depressed extended backwardly into the casing, movable indicators sliding inside the casing behind the front wall of same, aseries of mark ings similarly disposed on each indicator, a longitudinal opening extending over the whole length of said front wall, a series of transmitting levers consisting of one for each key connecting said indicators with the keys and causing an indicator to move downwardly in front of said opening when the corresponding key is depressed, a support pivotally mounted on the inner end of each key, a rod rigidly connected with said support, a number of weights removably inserted on said rod so as to act in 0 position to the pressure of the finger on said key, each Weight bearing a number indicating the force that has to be exerted on the outer end of the key to lift said weights and means to guide said weights during the movement imparted to them during the depression of the key, substantially as described.

3. A finger-exercising device to obtain and to preserve the normal relation between the individual natural strength of different fingers, comprising in combination: a casing, a keyboard with the keys to be depressed extended backwardly into the casing, movable indicators sliding inside the casing behind the front wall of same, a series of markings similarly disposed on each indicator, a longitudinal opening extending over the whole length of said front wall, a series of transmitting levers consisting of one for each key connecting said indicators with the keys and causing an indicator to move downwardly in front of said opening when the corresponding key is depressed, a support pivotally mounted on the inner end of each key, a rod rigidly connected with said support, a number of weights removably inserted on said rod, each weight bearing a number indicating the force that has to be exerted on the outer end of the key to lift said weight, a guiding rod parallel to the first rod and rigidly fixed on said support, a longitudinal bar maintained in said casing at right angles to the direction of said keys, said bar sup porting each guiding rod by means of openings in said bar, substantially as described.

4:. A finger-exercising device to obtain and to preserve the normal relation between the individual natural strength of different fingers, comprising in combination: a casing, a keyboard with the keys to be depressed extended backwardly into the casing, movable indicators slidin inside the casing behind the front wall 0 same, a series of markings similarly disposed on each indicator, a longitudinal opening extending over the whole length of said front wall, a series of transmitting levers consisting of one for each key connecting said indicators with the keys and causing an indicator to move downwardly in front of said openin when the corresponding key is depresse a support pivotally mounted on the inner end of each key, a rod rigidly connected with said support, a number of weights removably inserted on said rod, each weight bearing a number indicating the force that has to be exerted on the outer end of the key to lift said weight, a guiding rod parallel to the first rod and rigidly fixed on said support, a. longitudinal bar maintained in said casing at right angles to the direction of said keys, said bar supporting each guiding rod by means of openings in said bar and a removably mounted pivotal back-wall of the casing, the arrangement being such that the said weights can be easily removed and replaced after the backwall has been removed.

In testimony whereof I signed hereunto my name.

E. L. ROTH. 

